>>>I use winchester brass, sierra 155 grain matchkings and (what is known in the USAicon) AS Varget...or our 2208. I wont tell you the load but it is somewhere between 42 grains and 44 grains....<<<<

From my view there seems to be some very well informed loading going on here.

1. The .303 and the 7.62 Nato cases have very similar water capacities.
As you might recall from physics and especially chemistry PV = PV.
(With P = pressure and V= volume for gas.)

2. The manual data for the .308 Winchester (not talking about 7.62 Nato here) is about 10% higher than .303 data with similar bullets weights and Varget.

3. Whiterider's load is in the range of top loads for the .303 with a similar weight bullet.

His advantages are the use of more readily available 7.62 brass (AKA .308 for brass identification only), a closer fit between the chamber and the brass and a much larger selection of bullets.